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Hi All,
now I have found again the link to a cheap method to build
homemade solar cells:

http://www.mansolar.com/index.htm

As the summer comes now and the sun is shining again,
I will order all the chemicals to make such a homemade solar cell.

Also I will tryto modify these with my knowledge won in the
saltwater cells.

Have a look at the easy steps to make them here:


http://www.mansolar.com/make.htm

Needed is SnO2 for the conductive TCO layer and
TiO2 and some Bromberry juice( or different activator) and graphite.

One could make pretty large cells with this method !
Imagine 50x50 cm glasplates made by it.

Regards, Stefan.

P.S: If someone finds the efficiency for these cells, please post it.

Is there still any other conductive transparent metallic material
other than SnO2 ?

One would just need a metal-transparent conductive layer combination,
that has a bandgap together such, that light can knock off electrons
and push them  up the bandgap.
How much eV ( electronVolts) does normal sunlight have ?

http://www.solideas.com/solrcell/english.html


Here is another explanation how to do it.
Also checkout this additional tip:

soot coating as catalysator:
http://www.solideas.com/solrcell/phlab4.html

Here is more about the Graetzel cell in German language:

http://www.science-forum.de/download/graetzelober.pdf
very good informations there.

One thing to enhance the cell would be to use just a graphite plate as one
electrode ! This would avoid the need of the tinoxid plated glas plate at one side
and the light would go twice through the cell, cause the graphite also
reflects the light !

Regards, Stefan.

A cheap way to make a solar cell is with copper foil. Cut to the size you want.
First clean the foil good with steal wool to remove any oxide.
You heat the foil over a propane torch until the opposite side of the foil has a black oxide coating on it.
Don't over heat or the oxide will be burned off too.
Once the whole side is coated with this black oxide. You cool the foil slowly by removing it gradually from the flame.
Then you use steal wool and rub the black oxide coating off revealing a "red cuprous oxide" coating.
Be careful not to scratch the red coating. This red coating is the solar cell material.
This red coating is the negative lead and the shinny copper side that the flame was on is the positive lead.
To get a better contact a wire mesh can be applied to the red coating, like metal fly screen.
or better would be to put a light silver or gold coating on the red coating.
But the silver or gold coating must be thin enough to be transparant. 
Another method would be to paint conducting lines on the red coating with conducting paint,
like rear window defrost repair kits use. You could make a paint with Epoxy and graphite powder too.
Mix the graphite with the resin first to consistancy you want then add the hardener.

Another way to do it is to find a supplier of the  "red cuprous oxide powder" and apply this to copper foil.
Not sure how that is done, I just read in Japan someone was doing that.

Me personally, I live in Canada, and I would just go to Canadian Tire and pick up a solar pannel for $35.
and use a large magnifying lens sold at business deput used for reading. And make a solar pannel that way.
Or make a large mirror array to concentrate the sun on the cell.
But if you  are interested in makeing your own cell, now you know how.

hi,thanks for posting this, but the problem is,that this copperoxid cell does not put out much energy...at least in the old article scitoys...Can somebody try it with real copperoxid put onto a copperplate ? Thanks, regards, Stefan.
P.S. posting this from my new pocket pc via wap2 interface login...great.

Here is some info I came across on cheap and very simple plans(with plenty of room for personal improvements) for homemade solar cells

Build your own Cuprous oxide Solar Cell instructions:
The cell produces 50 microamps at 0.25 volts
Should be possible to improve drastically..!?

http://www.scitoys.com/scitoys/scitoys/echem/echem3.html#flatpanel
http://www.scitoys.com/scitoys/scitoys/echem/echem2.html

Cuprous oxide solar cells are just too weak in output.
We need to design something like the screen printing with the CdS and Tellurium.
Maybe we still find better and cheaper and less toxic materials that
can be screen printed onto a glas surface.
The most important thing is to get a very small thickness P-N Layer somehow
in the uMeter range and graphite powder or plates  can be used as the backside electrode
for current output.
Regards, Stefan.

Here is a very well documented video description
how to make a Graetzel cell from
conductive glas ( conductive indiumtinoxid (ITO) layer on the glas surface)
then put a paste of Titandioxide on it, heat it and
then put hibiskus tee or fresh blueberry or rasberry juice on it,
add some jod-Kaliumjodid electrolyte and have graphite as the other electrode
and you have a cheap solarcell...

http://www.hmi.de/it/zentral/multimedia/solar_energy/duenn_zellen/tee_film.html (http://www.hmi.de/it/zentral/multimedia/solar_energy/duenn_zellen/tee_film.html)

I will try to modify this and make it even cheaper...
substitute the ITO layer just with graphite also and
just mix graphite with Titandioxid and heat it and then put rasberry juice in
it and use this in a saltwater cell with the other electrode as Zink-Alu alloy..
As electrolyte I would probably then also use this jod-Kaliumjodid solution.
This would have the advantage that you need no expensive ITO coating of the
glas and have very cheap material with which you can build pretty big solar cells.
also these might have then already a open circuit voltage of about 1 Volts
and not just 0.45 Volts as the Graetzel cell...

Regards, Stefan.

Here are more infos to the easy to build Graetzel cell:

http://www.mansolar.com/function.htm
http://www.mansolar.com/bauen.htm
http://www.hmi.de/it/zentral/multimedia/solar_energy/duenn_zellen/tee_funktion.html

Efficiency for the TiO2 solar cell is 1 %
0,5V and 20A/m2, Power P = U x I = 0,5 x 20 = 10W/m2
2mA/cm2, 100 x 100 cm = 10000 cm2/m2, 2mA x 10000 cm2 = 20000mA/m2 = 20A/m2 (at full sun light)
Maximum practical power is 1000W/m2
Cell/Sun-Efficiency = 10W/1000W = 0,01, 0,01 x 100 (%) = 1%

http://www.solideas.com/solrcell/coatglas.html
http://www.solideas.com/papers/JCE98.pdf

Quote from: hartiberlin on February 15, 2006, 01:23:14 PM
Cuprous oxide solar cells are just too weak in output.
We need to design something like the screen printing with the CdS and Tellurium.
Maybe we still find better and cheaper and less toxic materials that
can be screen printed onto a glas surface.
The most important thing is to get a very small thickness P-N Layer somehow
in the uMeter range and graphite powder or plates  can be used as the backside electrode
for current output.
Regards, Stefan.

You can plate glass with most metals, but it will oxidize it in the process, its a process called glass fuming. If you melt a metal with a focused gas torch and aim the exhaust at preheated glass, the glass will obtain a thin transparent layer of fumed metal oxides in the glass. I hope this helps as I obtained this knowledge from an unrelated source, a guy I know blows glass and uses fuming to add unique color accents to his work.
:)

I wonder, if conductive glass is at all needed ?

Maybe it would be okay to have a small silver mesh as the upper
electrode.

Also the titandioxid heating is energywise expensive or mass
production...
Maybe one could just use it all in a water bath,
put the Titandioxid with the Dye in a water bath
and put it into the sunlight and have a graphite plate as
one electrode and a silver electrode as the other electrode ?

Maybe this will work as well to generate electricity from sunlight ?

We really must find a very cheap process, where only
a few cheap substances must be put together in a non toxic way and will generate electricity then from light.

Then we can reach a breakthrough in solar power applications.
So if you create a galvanic cell and have the electrolyte light sensitive
it might just work ?
Maybe colloidal silver will also work, as it is very light sensitive.

We have to find a liquid electrolyte, which will
help the sun to break electrons free and jump the voltage gap  barrier
between the 2 electrodes !

Any ideas ?
Regards, Stefan.

Progress on the TiO2 cell..!?
No figures of efficiency etc though.
Key factor: cost is one 10th of the price compared to silicon-based.

http://www.metaefficient.com/archives/renewable-power/innovative-solar-dyes-inexpensive-liquid-solar-power.html
http://masseynews.massey.ac.nz/2007/Press_Releases/04-04-07.html

More facts about the dye-TiO2 Gr?tzel cell.
A green dye has a lab efficiency of 7.1% in a liquid cell (71 Wm-2)
(11% in Am 1,5 - sunlight concentration ?).
No cell life-time data yet.
Australian company Dyesol sells all needed to build a test cell.

http://www.dyesol.com/index.php?page=intro

1:14 in this video to see what colloidal silver in looks like, it's just silver particals in water. This stuff is easy to make, and settles into a fine silver dust on the bottom of the glass, if left for awhile. Maybe this will make HHO in the cell, if it's in water, and the electrodes are connected.

would Silver particals aid the coloured dye?

Read this : www.keelynet.com/energy/tricksol.htm    ,
probably somebody search for more L.I. Belenyessy info
and about O.Barker
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=US5009243&F=0

S
  dL

http://www.google.com/patents?id=K-EbAAAAEBAJ&printsec=abstract&zoom=4&dq=5,009,243#PPP1,M1

oddly the pictures are screwed through google - I downloaded the PDF from here: http://www.pat2pdf.org/patents/pat5009243.pdf

Quote from: buzneg on April 26, 2007, 08:51:11 PM
1:14 in this video to see what colloidal silver in looks like, it's just silver particals in water. This stuff is easy to make, and settles into a fine silver dust on the bottom of the glass, if left for awhile. Maybe this will make HHO in the cell, if it's in water, and the electrodes are connected.

would Silver particals aid the coloured dye?

Which video did you mean ?
Please post a link.
Many thanks.

this one sorry

http://video.google.com/videoplay?docid=-3383948315844437935&q=bob+beck&total=316&start=0&num=10&so=0&type=search&plindex=0

test,I made a couple of copper oxide solar cells in the early 90's.fFound the instructions in a small book.
mine worked but power was always weak. the book said they were not very efficent.Triffid

You might get more power from them by using up to 10x the reflected light?(copper oxide,that is ).Triffid

thanks to whoever posted the screen printing process of making solar cells.Triffid

thanks to r8rchris,the ebook you posted had the info in it.Triffid

r8rchris,the directions to make screen printed solar cells in that pdf article is not complete.Because the japanese 1996 patent is not included.Does anyone here know the number to this patent?Page one of the pdf article does give instructions on how to use aluminum foil as the pos(+) side of the solar cell but you need the patent to tell you which chemicals to use to make the other layers with.However I do remember a link somewhere here on overunity.com to the japanese patent office.So If I can get a patent number
I might be in business.Triffid

I may have found the right patent(s) for the screen printing process of solar cells.I will need to take home the hard copies and see if I have a match.Triffid

The patent numbers I was given were 5928438 and 5726065.Triffid

Sorry I tried to match up the patent numbers 5928438 and 5726065,but no luck.I did relocate the link here to the japanese patent website so I still need the number for the japanese (1996) patent for screen printing solar cells.
The two patent numbers someone gave me are for the US patent office.
Triffid

I am so blind!!! The japanese patent was included in that report that was so generously supplied by someone here.Patent # is 5,538,903.Just more proof I'm not alway right or even close!Sorry!Triffid

Sorry r8rchris I skimmed that report too quickly the first time.Triffid

Ok here I go:The patent#5,538,903 is on screen printing solar cells onto glass.The pdf article that r8rchris so generously supplied  on page 1 tells you that you can screen print on aluminum foil in these manner:
5)metal ink(screen pattern)(neg electrode)
4)(n-type)mixed cadium sulphide and cadium chloride and proylene glycol.
    also known as the (CdS layer).
3)(p-type) an equi-mol  mixture of cadium(Cd) and tellurium(Te) powders with addition of CdCl2 and PG(proylene glycol).
2) carbon electrode layer with silver and indium mixed in.
1)aluminum foil (pos electrode)
I hope someone here makes these and posts their results.
Triffid

Whoever makes these here should read the pdf article and the patent r8rchris supplied for construction tips and sources for the chemicals.Also a propane outdoor grill is suggested to do the baking.The patent talks about using 600 degrees C. to bake with.Also mixing details are there plus concern about using vibration to reduce the bubbles in the pastes.When I first heard of this method it was about 10 years ago and some guy in kansas
used his kitchen oven at its max temp for like an hour.The landlord was concerned he was going to burn the apartment down and ordered him to stop.It was said in the article that his solar cells were working.Triffid

I am very interested in this, if someone can try it out and then give an easier step by step instruction guide, that would be great.  600 C is very hot!

Mark

r8rchris posted an ebook here in this thread that gives details on page 1 how to start the cell using aluminum metal.Then the patent #5,538,903 tells you what pastes are and how to mix them.there is a little more detail in the ebook that was posted on the patent pages.I have been looking for this patent for a couple of years.I have finally found it.I saw a section in the ebook on copper oxide solar cells  and thought pretty much the rest of the ebook was on that.Which is probably why I missed it in the first place.I was pretty much bummed out at whoever wrote it in the first place.I wondered why someone would wrote an ebook,charge $30.00 for it and not give details on the screen print method of making solar cells.But much to my delight When I went back to the ebook again I found the details were there afterall.The copper oxide stuff was in the middle of the report.So I assumed the rest of it was not there(the screen print method).To make these cells one would have to invest some time and money.You can make all you want for yourself,you just can't sell them to anyone else.Triffid

I heard that the dye solar cells had problems with leaking.Triffid

Are you going to make some?

Mark

What was the output supposed to be compared to a "normal" silicium-based solar cell?

And well, to anyone who wants to try it: watch the hell out with Cadmium!

I have no plans at the moment to make any.I might if I want to cover the whole roof of a house.Also anyone who wants to work with these chemicals should consult an MSDS manuel on the safety aspects.Before they ever start.Also if you have kids or pets at home forget it!!!I had a friend whose cat knocked over a jar of baking soda solution.He only had a mess to clean to clean up.If it had been acid or a base.Things would have been a lot more nasty.Triffid

I believe the output was at least 5% with some up to 10% ,But I am sure it would depend on the skill and experience of the person making them.I might also want to use heavy duty aluminum foil if I were making them.Triffid

Please keep us informed if you do decide to make them.

Thanks,
Mark

Will do.Triffid

www.backwoodshomemagazine.com has a lot of practical articles on solar and wind power for the offgrid home.You may have to dig a little for the articles.I found this from someone on myspace.Triffid

Sorry I meant www.backwoodshome.com   Triffid

Thanks for the info :)

I am going to try this method using HD aluminum Foil, baking outside, and then using menu size self sticking/sealing non reflecting laminating folding sheets. I found these for a dollar a piece and am excited about them. My question to you learned folks is where can I find these chemicals from? Do you have any links? Also I was hoping to use a car spray gun to spray the sheets instead of screen printing then a mouse sander under a steel plate  to vibrate the individual layers. Do you think this will significantly reduce the efficacy? Should I stick with the screen printing? 

Water,

Keep us informed of your progress!  I would think the screen printing method is used vs spraying maybe because of the viscosity of the ink?  Might be too thick to spray and if you try to cut it down like you said, you may lose efficiency of the chemicals to make energy.  But I am only guessing.  Good luck and I await your results  ;D

Mark

There is a solar ink out there that is capable of 17.4% efficient cells...

I am unable to find a supplier of the ink a manufacturer sure five star solar or something like that...

I hear you can purchase the ink from japan or something but have yet to come across the ink.

Would be nice to get some help on locating a supplier of the ink.

Thank you all that aid in this search.

-infringer-

http://www.Nanosolar.com and
http://www.konarka.com/
are using inks too.

So I hope we will see soon very cheap solarcells coming out.

Regards, Stefan.

P.S: I just saw, that Nanosolar has a new production facility
near Berlin, Germany where I live.

I will give them a call next week and ask,
if I could visit them and have a few cells and
make a report for overunity.com

I have a question on the dyes being used.  I'm pretty sure these dyes have very poor lightfastness.  They fade fast in light, especially uv exposure.  So are these cells going to have as short of a lifespan as the dye used?


Here's a pdf with good description and instructions.
http://www.camse.org/scienceonthemove/documents/DSSC_manual.pdf